Requirement Specification for Transportation Cyber Physical Systems

Software requirements errors are considered to account for a majority of software failures, and a number of accidents happen because of software requirements errors. The requirements specification of transportation cyber physical system is particularly critical because we must provide high safety of these transportation systems. Therefore, techniques to provide adequate requirements specification and to find errors early are of great importance. Transportation cyber physical systems contain three parts: physical parts, communication parts and computation parts. Existing methods cannot be well suited for requirement specification and modeling of transportation cyber physical systems. In this paper, we extend the AADL to model the behavior characteristic, continuous dynamic features and spatial-temporal requirements of transportation cyber physical systems. We propose a method to transform the rule of Cellular Automata to AADL model for modeling spatial-temporal requirements and we propose an approach to describe the continuous dynamic features in AADL and transform the Modelica model to AADL model. The proposed method is illustrated by Vehicular Ad-hoc Network.